This invention relates to a single ply, hydroentangled, nonwoven fibrous fabric that is comfortable, drapeable, flexible, non-linting, anti-static, non-flammable, strong, air permeable, quiet and is a bacterial barrier. More specifically, it relates to a microsized fabric wherein a latex has been worked below the surface of the fabric in order to impart the above-mentioned advantages.
A fabric as mentioned would have many applications, for example, hospital operating room surgical gowns, hospital draperies, upholstery and rain wear.
The present invention has the aforementioned properties and is particularly well suited for use as a surgical gown.
There is an ever present need in hospital operating rooms for a fabric that is comfortable, drapeable, flexible, non-linting, anti-static, non-flammable, strong, air permeable, quiet and is a bacterial barrier, for use as a surgical gown.
Prior art has tried to meet that need but has continuously fallen short of its goal.
U.S. Pat. No. 4,196,245, discloses a fabric that is composed of multiple plies, more specifically (3) three plies or more of different fibers. It is suggested in said patent that the prior art has succeeded in combining all the necessary physical properties, as mentioned in an earlier paragraph, that are needed in a fabric to make it a superior hospital surgical gown.
There are two important factors not considered by this prior art. The first factor is when fabrics are comprised of several plies of fiber, a certain degree of stiffness is inherent in the fabric. The second factor is that delamination of the fabric may take place when several plies of fiber are used.
If there is stiffness present in a fabric, there is a disadvantage built into the fabric, because with stiffness, the softness, drapeability, flexibility and good hand characteristics of cloth cannot be met with total satisfaction. Additionally, fabrics made in multiple plies have a tendency to delaminate for many reasons, but particularly due to poor adhesion between plies in the fabrication process. In addition, multiple ply fabrics are obviously more expensive to produce than the present invention, a single ply fabric.
U.S. Pat. No. 4,308,303, discloses a fabric, wherein a microporous plastic film is used as the base material. This patent suggests that a fabric has been found that has all the required prerequisites to meet the strict standards of a hospital surgical gown. However, there are disadvantages prevalent in this fabric which are based on its claim to filter bacteria. Patentee explains therein that water which has been inoculated with bacteria can be forced through the microporous plastic film used in the fabric. Water is forced through the microporous plastic film under moderate pressure, with sterile water being recovered on the other side of the film. The disadvantages to this prior art are: if the prior art fabric allows water and body liquids to penetrate the plastic film, these liquids will wet the skin of the wearer, causing the wearer to be uncomfortable; and if liquid is allowed to pass through the fabric, the inner side of the fabric will eventually become wet. When both the inside and outside of a fabric becomes wet, as may happen in a hospital setting, wicking of the liquid, with bacteria present, may take place from the exterior to the interior of the fabric. Once this condition exists, bacteria may well penetrate the fabric; come in contact with the wearer; and, thus subject the wearer to infection and/or contamination.
U.S. Pat. No. 4,188,446, discloses a nonwoven sheet material for use in hospitals which is comprised of cellulosic paper-making fibers and a binder which is applied therein in an amount sufficient to increase the strength of said sheet material. The increase in strength of this sheet material, as tested in a Mullen burst strength test, is significant. However, the test conducted was a dry test, and therefore the sheet material was not subjected to liquid. It is well known, however, that if a paper material is wetted by a liquid, the strength of such a material may deteriorate. This deterioration is due to the composition and short length of paper fibers, which, when wet have no strength because the bond between fibers is destroyed. Therefore, paper products, need to have binders for strength; but when binders are added for strength the paper product becomes non drapeable. The paper product is non drapeable because when the binder dries, it makes the product stiff. To make paper products drapeable, less binder is used, thus making a weak bond between paper fibers. If this is the case, the paper product when wetted will be sufficiently weakened to be inadequate for a hospital surgical gown.
The present invention has succeeded, where the prior art has not, by producing a strong single ply fabric with all of the physical properties mentioned in earlier paragraphs. The present invention is thus superior to prior art materials because it not only prevents liquid penetration, while permitting high air permeability, but acts as a bacterial barrier. In addition, the present invention due to a thermoplastic component, namely an acrylic latex in the froth, is heat sealable--a distinct advantage over prior art.